1639430694 has 144 divisors (see below), whose sum is σ = 4151674800. Its totient is φ = 465886080.

The previous prime is 1639430623. The next prime is 1639430719. The reversal of 1639430694 is 4960349361.

1639430694 is a `hidden beast` number, since 1 + 639 + 4 + 3 + 0 + 6 + 9 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 7158972 + ... + 7159200.

It is an arithmetic number, because the mean of its divisors is an integer number (28831075).

Almost surely, 2^1639430694 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1639430694, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2075837400).

1639430694 is an abundant number, since it is smaller than the sum of its proper divisors (2512244106).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1639430694 is a wasteful number, since it uses less digits than its factorization.

1639430694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451 (or 437 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 45.

The square root of 1639430694 is about 40489.8838476971. The cubic root of 1639430694 is about 1179.1372353725.

The spelling of 1639430694 in words is "one billion, six hundred thirty-nine million, four hundred thirty thousand, six hundred ninety-four".